Truck exhaust pipes are commonly mounted to extend vertically next to the cab to conform to regulations for hauling certain loads and to enhance the aesthetics of the vehicle, Trucks for hauling food products, for example, must expel the exhaust at a point that is positioned above the load to prevent the exhaust from contaminating the food products. Truckers also like to have bright, shiny chrome exhaust pipes next to the cab to enhance the appearance their trucks. Thus, it is generally desirable to mount exhaust pipes to extend vertically next to the cab.
When trucks have an air cab suspension, however, several problems arise in connection with vertically mounted exhaust pipes. A significant amount of vertical and lateral displacement occurs between vertically mounted exhaust pipes and the cab because the exhaust pipes are mounted to the frame of the vehicle while the cab is mounted to a separate air suspension system. The largest displacement between an exhaust pipe and a cab happens when frame "racking" occurs such that one frame member is displaced with respect to the other. Racking can cause up to 3.0" of vertical displacement between the pipes and the cab. A lesser amount of displacement occurs when the truck goes over bumps or potholes in the road surface. Accordingly, the upper end of vertical exhaust pipes should be secured to the outer wall of the cab to prevent damage to the pipes and cab.
Conventional mounting systems do not adequately secure vertical pipes to the cab. In securing the upper end of a vertical pipe to the cab, lateral displacement should be limited because it causes torsional stresses in the exhaust pipe and the exhaust pipe may bang against the cab in extreme conditions. Vertical displacement, on the other hand, should be freely allowed because restricting vertical displacement causes too quality of the ride in the cab. Conventional U-bolts and Fabreeka tethers do not adequately limit lateral displacement between the pipes and the cab. Conventional brackets that are fixedly attached to the cab and the pipe do not allow for sufficient vertical displacement. Accordingly it would be desirable to develop a connector for mounting a vertical exhaust pipe to a cab that adequately limits lateral displacement while allowing sufficient vertical displacement between the pipe and the cab.
Most conventional systems also transmit an excessive amount of noise to the cab. U-bolts and fixed brackets provide a highly conductive path for transmitting exhaust noise and engine vibrations from the exhaust pipe to the cab. Therefore, it would be desirable to develop a connector for mounting a vertical exhaust pipe to a cab that minimizes the transmission of vibrations from the exhaust pipe into the cab.